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Assessing Future Flooding Risk in a Coastal Lagoon Using Hydrogeological Approaches and Analysis of the 2021 Flood Event: A Case Study of Tasi-Tolu Lagoon, Dili, Timor-Leste
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作者 Mafaldo José Faria Marçal Ximenes Oktoviano Viegas Tilman de Jesus 《Journal of Water Resource and Protection》 2023年第6期276-298,共23页
This study aims to apply a hydrogeological approaches and analysis of the 2021 flood event of Tasi-Tolu Lagoon to achieve four specific goals. Firstly, the study seeks to determine the natural characteristics of the l... This study aims to apply a hydrogeological approaches and analysis of the 2021 flood event of Tasi-Tolu Lagoon to achieve four specific goals. Firstly, the study seeks to determine the natural characteristics of the lagoon, which include factors such as size, depth, water quality, and ecosystem composition. Secondly, the influence of precipitation on the water volume in the lagoon will be examined. This analysis involves assessing historical rainfall patterns in the region, as well as the amount and frequency of precipitation during the 2021 flood event. Thirdly, the hydrogeologic and geologic conditions of the lagoon will be evaluated. This involves examining factors such as the type and structure of the soil and bedrock, the presence of aquifers or other underground water sources, and the movement of water through the surrounding landscape. Finally, the study seeks to assess the risk of future flooding in Tasi-Tolu Lagoon, based on the insights gained from the previous analyses. Overall, this study’s goal is to provide a comprehensive understanding of the hydrogeological factors that contribute to flooding in Tasi-Tolu Lagoon. This knowledge could be used to inform flood mitigation strategies or to improve our ability to predict and respond to future flooding events in the region. 展开更多
关键词 Lagoon Characteristics Flooding Event Precipitation Shoreline Flooding Volume Hydrogeologic and Geologic Condition Assessing Future Flooding Risk of Tasi-Tolu Lagoon DILI TIMOR-lestE
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Improvement of Coding for Solar Radiation Forecasting in Dili Timor Leste—A WRF Case Study 被引量:1
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作者 Jose Manuel Soares de Araujo 《Journal of Power and Energy Engineering》 2021年第2期7-20,共14页
This paper investigates the accuracy of weather research and forecasting by improving coding for solar radiation forecasting for location in Dili Timor Leste. Weather Research and Forecasting (WRF) model version 3.9.1... This paper investigates the accuracy of weather research and forecasting by improving coding for solar radiation forecasting for location in Dili Timor Leste. Weather Research and Forecasting (WRF) model version 3.9.1 is used in this study for improvement purposes. The shortwave coding of WRF is used to improve in order to decrease error simulation. The importance of improving WRF coding at a specific region will reduce the bias and root mean square root when comparing to the observed data. This study uses high resolution based on the WRF modeling to stabilize the performance of forecasting. The decrease in error performance will be expected to enhance the value of renewable energy. The results show the root mean square error of the WRF default is 233 W/m<sup>2</sup> higher compared to 205 W/m<sup>2</sup> from the WRF improvement model. In addition, the Mean Bias Error (MBE) of the WRF default is obtained value 0.06 higher than 0.03 from the WRF improvement in rainy days. Meanwhile, on sunny days, the performance Root Mean Square Error (RMSE) of WRF default is 327 W/m<sup>2</sup> higher than 223 W/m<sup>2</sup> from the WRF improvement. The MBE of WRF improvement obtained 0.13 lower compared to 0.21 of WRF default coding. Finally, this study concludes that improving the shortwave code under the WRF model can decrease the error performance of the WRF simulation for local weather forecasting</span></span><span style="font-family:Verdana;">. 展开更多
关键词 Shortwave Radiation Solar Radiation Timor leste WRF Code Improvement
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A Case Study: Performance Comparison of Solar Power Generation between GridLAB-D and SAM in Dili Timor Leste
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作者 Jose Manuel Soares de Araujo 《Journal of Power and Energy Engineering》 2020年第8期1-22,共22页
Study of comparison of solar power generation between the GridLAB-D tool and System Advisor Model (SAM) in Dili, Timor Leste is presented in this paper. Weather Research and Forecasting (WRF) model is used to simulate... Study of comparison of solar power generation between the GridLAB-D tool and System Advisor Model (SAM) in Dili, Timor Leste is presented in this paper. Weather Research and Forecasting (WRF) model is used to simulate solar radiation for one calendar year from January to December 2014 using six-hourly interval 1° × 1° NCEP FNL analysis data. The one calendar year results from the WRF model will be used as input data for GridLAB-D and SAM to estimate the solar power generation. GridLAB-D is an open-source and analysis tool designed to operate the distribution power systems with a high-performance algorithm. System Advisor Model version SAM 2017.9.5 is used to estimate solar power performance with Photovoltaics (PVWatts)-<span style="font-family:;" "=""> <span style="font-family:;" "="">Commercial Distributed model. This model is designed to analyze the performance and the financing of renewable energy for electricity generation. The results show the lowest solar radiation is 512 W/m<sup>2</sup> obtained in June with an average monthly power of 20.6 kW and 30.55 kW generated from the SAM model and the GridLAB-D simulator, respectively. Meanwhile, the highest solar radiation is 1100 W/m<sup>2</sup>, 1112 W/m<sup>2</sup>, 1046 W/m<sup>2</sup>, and 1077 W/m<sup>2</sup> obtained in October, November, December, and January with an average monthly power of 55.72 kW, 62.44 kW, 56.65 kW, and 56.97 kW from the SAM model, in the other hand, 48.89 kW, 51.31 kW, 55.51 kW, and 57.18 kW generated by the GridLAB-D. Finally, the results show that the performance of the GridLAB-D and the SAM model was quite good because both model precisely presented values are almost closest to each other. This study proposes that the results of solar output power from both methods, GridLAB-D and SAM can be used to design grid-connected or stand-alone electric power projects to increase the quality of electricity generation in Dili, Timor Leste.</span></span> 展开更多
关键词 GridLAB-D System Advisor Model Solar Power Generation Timor leste WRF
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for fear(that)与lest有何区别?
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作者 赵丰跃 《语言教育》 2002年第2期46-46,共1页
关键词 SOMEONE for FEAR lest that himself UNLESS steal locked INJURED NOTES
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Combination of WRF Model and LSTM Network for Solar Radiation Forecasting—Timor Leste Case Study
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作者 Jose Manuel Soares de Araujo 《Computational Water, Energy, and Environmental Engineering》 2020年第4期108-144,共37页
A study of a combination of Weather Research and Forecasting (WRF) model and Long Short Term Memory (LSTM) network for location in Dili Timor Leste is introduced in this paper. One calendar year’s results of solar ra... A study of a combination of Weather Research and Forecasting (WRF) model and Long Short Term Memory (LSTM) network for location in Dili Timor Leste is introduced in this paper. One calendar year’s results of solar radiation from January to December 2014 are used as input data to estimate future forecasting of solar radiation using the LSTM network for three months period. The WRF model version 3.9.1 is used to simulate one year’s solar radiation in horizontal resolution low scale for nesting domain 1</span><span style="font-family:""> </span><span style="font-family:Verdana;">×</span><span style="font-family:""> </span><span style="font-family:Verdana;">1 km. It is done by applying 6-hourly interval 1</span><span style="font-family:Verdana;">&ordm;</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">×</span><span style="font-family:Verdana;"> 1</span></span><span style="font-family:Verdana;">&ordm;</span><span style="font-family:""><span style="font-family:Verdana;"> NCEP FNL analysis data used as Global Forecast System (GFS). LSTM network is applied for forecasting in numerous learning problems for solar radiation forecasting. LSTM network uses two-layer LSTM architecture of 512 hidden neurons coupled with a dense output layer with linear as the model activation to predict with time steps are configured to 50 and the number of features is 1. The maximum epoch is set to 325 with batch size 300 and the validation split is 0.09. The results demonstrate that the combination of these two methods can successfully predict solar radiation where four error metrics of mean bias error (MBE), root mean square error (RMSE), normalized MBE (nMBE), and normalized RMSE (nRMSE) perform small error distribution and percentage in three months prediction where the error percentage is obtained below the 20% for nMBE and nRMSE. Meanwhile, the error distribution of RMSE is obtained below 200 W/m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> and maximum bias error is 0.07. Finally, the values of MBE, RMSE, nMBE, and nRMSE conclude that the good performance of the combination of two methods in this study can be applied to simulate any other weather variable for local necessary. 展开更多
关键词 COMBINATION LSTM Solar Radiation WRF Timor leste
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Herpetological Diversity of Timor-Leste: Updates and a Review of Species Distributions
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作者 Mark O'SHEA Caitlin SANCHEZ +6 位作者 Andrew KATHRINER Sven MECKE Venancio LOPES CARVALHO Agivedo VARELA RIBEIRO Zito AFRANIO SOARES Luis LEMOS DE ARAUJO Hinrich KAISER 《Asian Herpetological Research》 SCIE CSCD 2015年第2期73-131,共59页
We report the results of five herpetological surveys during 2011-2013 that included visits to all districts of Timor-Leste (Aileu, Ainaro, Baucau, Bobonaro, Dili, Covalima, Ermera, Laut6m, Liquiga, Manatuto, Manufahi... We report the results of five herpetological surveys during 2011-2013 that included visits to all districts of Timor-Leste (Aileu, Ainaro, Baucau, Bobonaro, Dili, Covalima, Ermera, Laut6m, Liquiga, Manatuto, Manufahi, Viqueque) except the Oecusse exclave. Our fieldwork culminated in the discovery of one putative new frog species (genus Kaloula), at least five putative new lizard species (genera Cyrtodactylus, Cryptoblepharus, and Sphenomorphus), and two putative new snake species (genera Stegonotus and Indotyphlops). In addition, we present new distribution records of amphibians and reptiles for 11 of the country's 12 contiguous districts, along with additional natural history data. Results from our surveys increase the number of amphibian and reptiles known to occur in Timor-Leste from 22 species before our surveys began to over 60, including over 20 as yet undescribed species. 展开更多
关键词 TIMOR-lestE Kaloula Cyrtodactylus Eremiascincus Stegonotus
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First Update to Herpetofaunal Records from Timor-Leste
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作者 Mark O'SHEA Caitlin SANCHEZ +6 位作者 Scott HEACOX Andrew KATHRINER Venancio LOPES CARVALHO Agivedo VARELA RIBEIRO Zito AFRANIO SOARES Luis LEMOS DE ARAUJO Hinrich KAISER 《Asian Herpetological Research》 SCIE 2012年第2期114-126,共13页
Herpetological surveys of locations in six districts of Timor-Leste(Dili, Baucau, Ermera, Liqui a, Manatuto, Viqueque) during 2010 led to the discovery of a new, high-altitude species of Cryptoblepharus from Ermera Di... Herpetological surveys of locations in six districts of Timor-Leste(Dili, Baucau, Ermera, Liqui a, Manatuto, Viqueque) during 2010 led to the discovery of a new, high-altitude species of Cryptoblepharus from Ermera District, a new country record(Hemidactylus cf. tenkatei), and the recording of two previously unvouchered species(Python r. reticulatus and Liasis m. mackloti). In this article, we summarize these new records and present numerous new district records for Timor-Leste and four records for road-killed snakes seen in West Timor(Indonesia). With the addition of the results from our 2009 survey, the update presented herein increases the confirmed number of amphibian and reptile species for Timor-Leste to 47. 展开更多
关键词 HERPETOFAUNA biodiversity TIMOR-lestE West Timor WALLACEA Cryptoblepharus Hemidactylus cf.tenkatei
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Effects of Slash-and-Burn Practices on Soil Quality at Different Landscape Positions in the Raumoco Watershed, Municipality of Lautem, Timor-Leste
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作者 Delfim Da Costa Decibel V. Faustino-Eslava Rico C. Ancog 《Open Journal of Ecology》 2022年第7期483-498,共16页
Slash-and-burn practices used by farmers in prior growing periods could affect soil quality, particularly topsoil properties. This study aimed to assess soil biophysical and chemical properties at different landscape ... Slash-and-burn practices used by farmers in prior growing periods could affect soil quality, particularly topsoil properties. This study aimed to assess soil biophysical and chemical properties at different landscape levels within the watershed site. Soil samples were collected by a core method in the topsoil layer in slash-and-burn sites. Field analysis was on bulk density and porosity by the gravimetric method, while laboratory analysis was done on organic matter by the Loss on Ignitions Method and other macronutrients for crops (total nitrogen, phosphorus availability, and potassium availability) followed standard analytical methods. To see if there was a significant difference between sites, DMRT 5% was used. The results of the study showed slash-and-burn practice affects soil physical properties such that high bulk density in upstream, midstream, and downstream ranged from 1.55 g/cm<sup>3</sup> to 1.71 g/cm<sup>3</sup>, 1.55 g/cm<sup>3</sup> to 1.80 g/cm<sup>3</sup>, and 1.38 g/cm<sup>3 </sup>to 1.79 g/cm<sup>3</sup> respectively. Poor porosity in upstream, midstream, and downstream ranged from 33.91% to 40.06%, 30.38% to 41.75%, and 30.91% to 46.65%, respectively. Organic matter content was low in the upstream, midstream, and downstream areas, ranging from 2.86% to 3.39%, 2.58% to 3.88%, and 2.91% to 3.88%, respectively. However, soil pH remains neutral, and nitrogen levels are low but near-optimal in the upstream and very low in the midstream and downstream. Phosphorus is extremely high upstream but very low in midstream and downstream. However, potassium remains at a low level close optimum level in the entire watershed. 展开更多
关键词 TIMOR-lestE Raumoco Watershed Slash and Burn Farming
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An Overview of the Geological Control on Groundwater Potential in Lacamutu River, Alaua Kraik Area, Baucau Municipality, Timor-Leste
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作者 Mafaldo Jose Faria Marcal Ximenes +1 位作者 Jonas Sambi da C. Amaral Amandio da Silva 《Journal of Water Resource and Protection》 CAS 2022年第10期680-697,共18页
Timor island has a tropical climate with relatively little rainfall and surface water is often not available throughout the year with groundwater relied on to fulfill daily domestic necessities. Geological reconnaissa... Timor island has a tropical climate with relatively little rainfall and surface water is often not available throughout the year with groundwater relied on to fulfill daily domestic necessities. Geological reconnaissance mapping, hydrogeological investigation, and resistivity survey were undertaken in this study to systematically understand the hydrogeologic system (e.g., aquifer system, hydrostratigraphic units, groundwater flow direction) and its potentiality for water supply to human consumption in Alaua Kraik area, Baucau Municipality, Timor-Leste. Res2DInv, Dips 5.1, Surfer 16, Global Mapper 13, and ArcGIS 10.6 software was used to create geological reconnaissance maps, resistivity interpretation profile lines, and a hydrostratigraphic model. Rainfall precipitation, rainfall intensity, maximum rate of runoff and infiltration data are also used to interpret the groundwater potential in the study area. Two rock units occur in the study area;permeable alluvial deposits which unconformable overlie impermeable interbedded red marl-chert and calcareous shale. Structurally the area comprises the Lacamutu anticline, thrust fault, left slip fault, and normal right slip fault. Resistivity lines indicate three (3) types of lithologies: alluvial deposit, an intercalated layer of red marl-chert, calcareous shale and wet calcareous shale. The alluvial deposit and red marl-chert layer intercalated with calcareous shale units are classified as a hydrostratigraphic unit of intergranular and localised aquifer systems with low productivity. The groundwater flows through the existing fractures of the shear joint and tends to flow towards the left slip fault plane zone from the North to South direction. Much of the rainwater in the study area is most likely intercepted, evaporated, and or transpiration as opposed to running off and infiltrating into the ground. The permeable and heavily fractured impermeable rock units in the study area have good porosity but low permeability and represent poor aquifers. The springs and Lacamutu River have low discharge and are generally dry in the dry season as it does not have an adequate aquifer that can accumulate and pass groundwater with significant volumes even if the rainfall in the study area is classified as moderate rainfall. 展开更多
关键词 Local Geology Resistivity Interpretation Groundwater Potential RAINFALL Lacamutu River—Alaua Kraik Area—Timor-leste
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增程式电动汽车能耗测试仿真试验研究 被引量:1
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作者 李峰 丁玲 +2 位作者 史育海 李岳兵 蔡鑫鑫 《汽车科技》 2023年第1期44-50,共7页
增程式电动汽车采用与传统混合动力电动汽车同样的能耗测试标准,但二者在工作原理和系统构架等方面存在显著差异。通过搭建增程式电动汽车仿真模型,采用全球统一的轻型车测试循环(WLTC)工况进行电量消耗模式(CD)和电量保持模式(CS)的能... 增程式电动汽车采用与传统混合动力电动汽车同样的能耗测试标准,但二者在工作原理和系统构架等方面存在显著差异。通过搭建增程式电动汽车仿真模型,采用全球统一的轻型车测试循环(WLTC)工况进行电量消耗模式(CD)和电量保持模式(CS)的能耗仿真试验,再基于实车试验室数据对仿真模型进行对比验证。最后,开展采用中国轻型汽车行驶工况(CLTC)的能耗仿真试验,分析增程式电动汽车在两种不同工况下的能耗表现。结果表明:采用仿真手段能较好地实现对增程式电动汽车的能耗测试,且综合结果与试验室数据较为相符,采用CLTC工况的能耗测试表现要显著优于WLTC工况的能耗测试表现。 展开更多
关键词 增程式电动汽车 能耗测试 仿真试验 循环工况 纯电利用系数
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激光光斑的高斯拟合 被引量:29
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作者 孔兵 王昭 谭玉山 《激光技术》 CAS CSCD 北大核心 2002年第4期277-278,共2页
给出了激光光斑的高斯拟合及其改进算法 ,实验表明 ,拟合曲线与原始实验数据达到很好的逼近 。
关键词 激光 光斑 高斯拟合 最小二乘原理 算法
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特高压变压器模型漏感参数的稳态识别方法 被引量:28
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作者 邓祥力 高亮 +2 位作者 刘建峰 张哲 尹项根 《电工技术学报》 EI CSCD 北大核心 2014年第5期254-260,共7页
针对变压器参数辨识算法在系统稳态运行时变压器绕组参数具有不可辨识性的特殊问题,本文提出了全新的参数辨识算法模型和基于自相关函数统计量的参数辨识结果判别标准。并使用EMTP仿真工具,依据动模实验室特高压输电系统,搭建了特高压... 针对变压器参数辨识算法在系统稳态运行时变压器绕组参数具有不可辨识性的特殊问题,本文提出了全新的参数辨识算法模型和基于自相关函数统计量的参数辨识结果判别标准。并使用EMTP仿真工具,依据动模实验室特高压输电系统,搭建了特高压输电系统仿真模型,分别仿真了特高压变压器空载投入、区外故障、区内故障和正常运行时的各种运行状态,验证了在各种工况下,基于新模型的参数辨识算法都能够精确辨识出变压器绕组参数的真实值。 展开更多
关键词 励磁涌流 参数辨识 特高压变压器保护 最小二乘法
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基于最小二乘法的车辆瞬态燃油消耗估计 被引量:10
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作者 张金辉 李克强 +1 位作者 徐彪 李红 《汽车工程》 EI CSCD 北大核心 2018年第10期1151-1157,共7页
精确的车辆瞬态燃油消耗估计是车辆节能控制研究的基础,稳态燃油消耗模型受燃油发动机的非线性工作特性、驾驶员的驾驶习惯、车辆行驶的环境、车辆行驶状态、车辆负载等多种因素影响,计算的瞬态燃油消耗与实际燃油消耗偏差较大,现有瞬... 精确的车辆瞬态燃油消耗估计是车辆节能控制研究的基础,稳态燃油消耗模型受燃油发动机的非线性工作特性、驾驶员的驾驶习惯、车辆行驶的环境、车辆行驶状态、车辆负载等多种因素影响,计算的瞬态燃油消耗与实际燃油消耗偏差较大,现有瞬态油耗模型参数不易标定,因此本文中通过车辆速度与加速度构建了一种新的瞬态燃油消耗估计模型。采用最小二乘法对模型中的参数进行求解,为进一步降低瞬态燃油消耗率的估计偏差,引入指数速度衰减的加权因子,即采用带指数衰减因子的最小二乘法求解油耗模型中的参数,并通过实车试验对瞬态油耗估计方法进行验证。试验结果表明,基于最小二乘法的油耗模型可精确地估计车辆瞬态油耗,带指数速度衰减因子的最小二乘法可进一步降低油耗模型的油耗估计偏差,且估计精度受车辆行驶状态和道路环境等因素影响较小。 展开更多
关键词 燃油消耗估计 瞬态油耗模型 最小二乘 带衰减因子的最小二乘
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光纤光栅Bragg波长的高斯曲线拟合求法 被引量:22
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作者 吴付岗 张庆山 +1 位作者 姜德生 何伟 《武汉理工大学学报》 EI CAS CSCD 北大核心 2007年第12期116-118,共3页
利用最小二乘法对观测的数据进行曲线拟合,由于保证了离差平方和取得最小,因此少数数据点的干扰对拟合曲线的参数影响不大,各参数值的大小主要取决于整体观测值。将得到的FBG反射谱采样值,采用高斯曲线拟合的方法进行回归分析,通过拟合... 利用最小二乘法对观测的数据进行曲线拟合,由于保证了离差平方和取得最小,因此少数数据点的干扰对拟合曲线的参数影响不大,各参数值的大小主要取决于整体观测值。将得到的FBG反射谱采样值,采用高斯曲线拟合的方法进行回归分析,通过拟合得到的高斯函数参数值来获得相应Bragg波长值,降低了光噪声对光纤Bragg光栅中心波长测量的影响。 展开更多
关键词 光纤BRAGG光栅 反射谱 高斯拟合 最小二乘法
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金银花提取物抑菌作用的实验研究 被引量:49
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作者 管仲莹 赵金明 林巧智 《中国现代医生》 2009年第15期150-151,153,共3页
目的观察金银花的体外抑菌作用。方法采用对不同菌株的敏感性及最小抑菌浓度测定法进行体外抑菌试验。结果肺炎链球菌、铜绿假单胞菌对金银花提取物有较强的敏感性,抑菌圈直径大于19mm,金黄色葡萄球菌、大肠埃希菌、无乳链球菌、化脓链... 目的观察金银花的体外抑菌作用。方法采用对不同菌株的敏感性及最小抑菌浓度测定法进行体外抑菌试验。结果肺炎链球菌、铜绿假单胞菌对金银花提取物有较强的敏感性,抑菌圈直径大于19mm,金黄色葡萄球菌、大肠埃希菌、无乳链球菌、化脓链球菌、痢疾志贺菌对金银花提取物中度敏感;最低抑菌浓度小于0.125g/mL。结论金银花提取物具有一定的抑菌作用。 展开更多
关键词 金银花提取物 抑菌试验 抑菌作用
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面向软件可靠性测试数据生成的剖面构造技术 被引量:11
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作者 艾骏 陆民燕 阮镰 《计算机工程》 EI CAS CSCD 北大核心 2006年第22期7-9,45,共4页
软件可靠性测试是软件可靠性工程中的一项重要工作内容,通过软件可靠性测试积累的软件失效数据可以为软件可靠性的评估、验证提供重要的度量依据。针对传统的基于操作剖面的可靠性测试方法对实时嵌入式软件的适用性差、测试难以实施的情... 软件可靠性测试是软件可靠性工程中的一项重要工作内容,通过软件可靠性测试积累的软件失效数据可以为软件可靠性的评估、验证提供重要的度量依据。针对传统的基于操作剖面的可靠性测试方法对实时嵌入式软件的适用性差、测试难以实施的情况,在操作剖面的基础上提出了一种层次化网络体系结构的使用剖面的概念,并研究了构造使用剖面的系统方法,以及根据使用剖面生成用于实时嵌入式软件可靠性测试操作序列的方法。该方法适用于实时嵌入式软件,对其它非实时软件也具有参考价值。 展开更多
关键词 软件 可靠性 软件测试 操作剖面 使用剖面
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铝的阳极氧化工艺与氧化膜性能 被引量:13
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作者 王振林 唐丽文 杨惠 《轻合金加工技术》 CAS 北大核心 2010年第2期45-48,55,共5页
采用硫酸直流阳极氧化在铝表面形成氧化膜,并进行了表面成分深度分布、物相结构、形貌、显微硬度表征。结果表明,氧化膜为无定型Al2O3和Al的夹杂层,O和Al的分布由表及里呈反向变化,硫酸根离子渗入氧化层并在界面处富集,氧化膜的显微硬... 采用硫酸直流阳极氧化在铝表面形成氧化膜,并进行了表面成分深度分布、物相结构、形貌、显微硬度表征。结果表明,氧化膜为无定型Al2O3和Al的夹杂层,O和Al的分布由表及里呈反向变化,硫酸根离子渗入氧化层并在界面处富集,氧化膜的显微硬度较基体有了显著提高。通过正交试验优化了试验工艺条件。 展开更多
关键词 阳极氧化 氧化膜 显微硬度 正交试验
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声表面波液相金属离子传感器 被引量:9
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作者 叶学松 樊海涛 +2 位作者 杨明艳 康峰 王平 《传感技术学报》 CAS CSCD 2004年第2期280-284,共5页
以 36° -YXLiTaO3为基底的双通道声表面波 (SH -SAW)液相金属离子传感器 ,在LabView测试平台下采用流动注射的方法研究了该系统在液相金属离子检测和分析中的原理和应用。实验表明 ,传感器稳态的输出频率反应了待测溶液的电导率 ,... 以 36° -YXLiTaO3为基底的双通道声表面波 (SH -SAW)液相金属离子传感器 ,在LabView测试平台下采用流动注射的方法研究了该系统在液相金属离子检测和分析中的原理和应用。实验表明 ,传感器稳态的输出频率反应了待测溶液的电导率 ,数据经拟和处理 ,误差 <0 2 4 % ;传感器的检测下限为 10 - 5mol/L ;对于两种金属离子的混合溶液 ,传感器的瞬态响应反映了待测溶液中所含的离子成份 ,采用偏相关分析 (PLS)算法可以有效识别待测溶液中离子成份的比例 ,识别误差 <3%。研究表明 ,通过进一步的优化设计 ,这种新型的液相金属离子分析仪器具有重复性好、灵敏度高、体积小和适合在线实时检测等方面的优点。 展开更多
关键词 SH—SAW PLS 液相检测 金属离子
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一种用于动态视频超分辨率的多尺度最小二乘仿射块匹配图像配准方法 被引量:9
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作者 王素玉 卓力 +1 位作者 沈兰荪 李晓光 《电子与信息学报》 EI CSCD 北大核心 2009年第3期542-545,共4页
动态视频的超分辨率复原中,连续各帧图像间的精确匹配具有非常重要的意义。该文提出一种基于多尺度最小二乘仿射块匹配的图像配准方法。首先定义了一个指标Dmv来衡量图像的整体和局部匹配效果,并以此为基础设计了一种多尺度块选择机制,... 动态视频的超分辨率复原中,连续各帧图像间的精确匹配具有非常重要的意义。该文提出一种基于多尺度最小二乘仿射块匹配的图像配准方法。首先定义了一个指标Dmv来衡量图像的整体和局部匹配效果,并以此为基础设计了一种多尺度块选择机制,根据图像的运动情况选择匹配块大小,以兼顾图像中运动平坦和非平坦区域的匹配效果。与传统的块匹配方法不同,该文采用基于仿射模型的最小二乘配准方法实现各图像块的匹配,并通过修正步长的归一化处理解决了不同大小图像块在匹配时的收敛问题,从而在提高参数估计精度的同时降低了算法的运算量。最后,通过实验对算法的匹配性能及其对超分辨率复原算法整体性能的影响进行了测试。实验结果表明,该方法不仅可以实现更为准确的运动估计,当用于最大后验概率MAP超分辨率复原算法时,能够进一步有效提高算法的复原性能和实现速度。 展开更多
关键词 图像配准 动态视频 仿射模型 最小二乘估计 块匹配
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环保投资与经济增长的协整及因果关系检验——基于1981~2005年的数据分析 被引量:16
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作者 胡海青 李建 张道宏 《科技进步与对策》 CSSCI 北大核心 2008年第7期99-101,共3页
使用Granger因果关系检验法检验我国1981~2005年间的环保投资增量和GDP增量的因果性,发现GDP增量的变化是引起环保投资增量变化的原因,通过协整和误差修正模型对两者的长期和短期关系进行了研究。研究发现,我国环保投资增量与GDP增量... 使用Granger因果关系检验法检验我国1981~2005年间的环保投资增量和GDP增量的因果性,发现GDP增量的变化是引起环保投资增量变化的原因,通过协整和误差修正模型对两者的长期和短期关系进行了研究。研究发现,我国环保投资增量与GDP增量间存在着可靠的协整关系。这说明随着我国经济的快速持续发展,保持两者的均衡发展具有重要的意义,最后提出基本结论以及相关的政策建议。 展开更多
关键词 环保投资增量 GDP增量 协整分析 误差修正模型
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